Reference: http://www.v6accord.com/forums/showt...threadid=14482

I guess, I need to run an oil analysis on my CLS

 

I'd be concerned with high tin and/or lead... but it looks good so far...

I have gotten two different stories on the bearing material... so...

But, lead is in there...

http://dwolsten.tripod.com/articles/sep93a.html

"...To remedy the problem, a team of Honda metallurgists/engineers created a highly seizure-resistant overlay on the bearing's sliding surface using a unique electrodepositing of tetra-methyl lead, Pb (h00). The highly oriented Pb surface has a composition of myriad minuscule pyramids, which possesses outstanding "wettability" or lubricant-retaining properties. Honda claims it has given a 30% or higher increase in the anti-seizure parameter, PV, than a surface with conventional deposits.

In August 1991, Soichiro Honda passed away. The Wako engineers' way of expressing homage to the late founder was to win the next Formula One race–the Hungarian Grand Prix of that year. The new highly oriented crystal bearings were used in the Honda V12 which propelled a McLaren racer to its long overdue victory.

The beauty of this bearing was that it was cost-competetive. It was subsequently adopted in the Legend's new longitudinal V6 engine..."

4 bangers are mentioned as well...

The other article was more up-to-date, but...




I lost the links to some other ones... and will have to look around some more.

 

I wouldn't think the pulley's would contribute to engine bearing wear. I'd be more concerned about a crank fracture (which wouldn't have any advance warning.).

 

They aren't gonna wear your engine out in the 5k miles you've had them. They could wear it out over a long term amount of time. This is why people who don't care and will be ditching their car in a year or two can go right ahead and slap on those UR pulleys without concern. It's only a long-term thing for us who plan to be 100k+ milers.

 

 

How does the pulley affect the harmonic balance of the crank?

 

The UR pulley REPLACES the harmonic damper which is supposed to stop nasty vibrations in the engine. It's a two sided debate. AEM says removing it is VERY bad, UR says no long term effects have ever been seen by removing the damper.

So either you get this:
1) Crank piles up from the extra vibration (if AEM is right).
2) You just get more engine vibration (if UR is right).

My friend reads the F-Body forums (Camaro, T/A) and one user snapped his crank by over-tightening the alternator! Hearing that freaks me out, so I'm sticking with 1, above.

But, to each his own.

 

i'm going to wait and do the pulleys as one of my later mods to see if anyone has any problems, the ur pulleys have amazing gains, i hope ur is right and aem is not.

 

what if you keep replacing new pullies every year or so?..

 

I'm thinking if you tighten it to the right amount and give it some play to vibrate back and forth without hitting the laternator pulley hard then yo ushould be fine... it's kind of like a spinning centrifuge, if you weight it equally on all sides then it won't vibrate at all. Basically when something like the guy with the alternator pulley cracking happens it's b/c of poor quality in workmanship. If the pulley was perfectly weighted then most likely it would not vibrate at all.

 

UR claims that ther Pulleys are 0 gram balanced.

 

I've got some books on electric motor design and one of the issues that is clearly addressed is bearing wear from torsional and balance issues..

If you have a completely homogenous bar of material, you can sometimes keep the twist from causing any lateral movement.

Think of a sway bar (torsion bar) and the normal thought is that they only twist... well, depending on how that perfectly round bar was made (how even the grain is) you can find it bowing and bending a bit. Any ADDITIONAL bearings would get some side loading.

Now back to the crank -- it is not going to be perfectly homogenous AND it has a structure that looks like a bent paper clip. Think about this: when you twist one end of crank relative to the other end, it wants to apply a side load on its bearings (this in addition to the force of the explosion and any out-of-balance forces).

So, perhaps some of the people out there are saying the bearing load is very small. It depends! To know would require some good tests and instrumentation (and it isn’t cheap). However, if you can ever manage to grab a paper clip and bend it into a shape to simulate 1 crank throw (a one cylinder engine) with two main bearings, you can twist one end and see the applied torque/twist turn into a lateral movement; this is a side load.


Now to address the issue of "oil analysis"... Can it prove or disprove that a crank or bearing is going to fail? I'm not sure about this. OTOH, if Nashau had gotten some really horrific tin/lead readings and the cars with UR pullies were only seeing a lot of “wear”, this wouldn’t be reassuring. So, at the very minimum, the oil test, isn’t going to hurt, and at least would show that serious damage is not being done and depending on the type and degree of torsional vibration, a pulley mod can have wildly varying effects on an engine durability. IF nothing else, it seems to be worth doing to monitor the engine condition, and would certainly show if anything really nasty was going on…



RE: the crank failure – yes, the failure do to the nature of the vibrations is very similar to chaos theory (non-linear dynamics) in some respects. It is possible to keep increasing the stress up to a point, and then have a catastrophic failure with minimal warning.

 

It's not the pullies that will break rather the bearings, crank etc.,

 

To blackstone labs:
==============
Hi,

I own a 2001 Acura CL Type-S Auto. I have some bolt-on aftermarket performance mods. Since, now I am now close to 43,000 miles, I am due for an engine oil and Automatic transmission fluid change at 45,000 miles.

So please could you send me Free Oil Collecting kits for engine oil and the ATF?

Thanks.

 

Again, in reality what you run into with our car is if you're not going to have the pulley on there more than (who knows... probably around) ~35k miles, it might (should) be okay. If it's longer term than that, you could (probably) run into trouble. To put it simply, the longer you run their pulley the more likely you are to incur a problem.

 

Are you suggesting that the vibration will cause fatigue that will lead to catastrophic failure of the crankshaft?

 

That's the thought. Will it happen? Who knows.

 

I would be surprised to see anything that definitive. I would not surprise me to find that motors without harmonic balancers wore out sooner because they did not run as smoothly.

 

Eric,

I don't understand how the pully would contribute to crank problems, unless the overall balancing of the crank is in part dependent on the OEM pully design to add final balancing. I would be shocked if it is.

Also, the bearing issue should also not a problem if the UR Pully is properly balanced rotationally and dimentionally/cross-sectionally.

Thoughts?

RUF

 

The crank itself is balanced, it's just the whole rotation of a motor is not smooth. You have pistons being shoved in and out at weird angles to the crank. When a cylinder is fired, it forces the piston back down, which isn't the nicest motion.

The damper is supposed to absorb a bunch of these transient vibrations.